It's not often you hear a politician so upbeat about having lost an election. But last night, Nigel Farage, leader of the UK Independence party was ebullient.

It looks as though this will be our best byelection by a country mile. It's a big night for Ukip. I suspect we probably won't quite do enough to beat Labour but with this result here and another byelection up the road in Middlesbrough where I think we're also going to come second, this party is going places.

He was right – the Ukip candidate didn't beat Labour in Rotherham, but it came second there and in Middlesbrough, and took third place in Croydon North.

Ukip's gains were as much the coalition's losses, however. Whereas Labour increased its share of the vote by 1.62% in Rotherham, the Conservatives were down 11.32% and the Liberal Democrats 13.87%. The latter managed only 451 votes.

Thomas Pascoe, in a Telegraph blog, saw it as a bleak moment for both of the parties of government.

Tonight's byelection results tell us that the coalition is already in real trouble when it comes to the next general election. It is not so much the fact Labour increased its vote share while holding Croydon North, Middlesbrough and Rotherham which ought to concern David Cameron and Nick Clegg, it is that each party has lost its reason for being.

Frustration with the incumbents, and a week of unprecedented publicity – the fostering furore and talk of a pact with the Conservatives – seem to have played into Ukip's hands. But how much can we believe Farage when he says, "The political establishment is just going to have to wake up to the fact that Ukip is here and here to stay as a significant and rising mainstream part of British politics"? Is Ukip a flash in the pan, or could it one day take its place as the new third party?

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